Test Instruments & Measuring Devices
Voltmeters are used extensively in industry where the surveillance of input and/or
output voltages is vital for plant operation.
STATE the electrical parameters measured by each of
the following in-place measuring devices:
EXPLAIN how the following electrical test equipment
and measuring devices are connected to a circuit:
A simple DC voltmeter can be constructed by placing a resistor (RS), called a multiplier, in series
with the ammeter meter movement, and marking the meter face to read voltage (Figure 4).
Voltmeters are connected in parallel with the load (RL) being measured.
Figure 4 Simple DC Voltmeter
When constructing a voltmeter, the resistance of the multiplier must be determined to measure
the desired voltage. Equation (14-1) is a mathematical representation of the voltmeters